June, 1932] Electricity on New England Farms 49 



Complicated Rate Structure. 



Another form of rate structure that has been used in the rural j&eld 

 is one in which the costs of all items entering into the generation of 

 the current and its delivery to the customer form the basis of a very- 

 complicated formula for arriving at the cost per kilowatt hour. 



Such a rate as this is practically impossible of explanation to the 

 average layman, and is, therefore, apt to be a continual cause of dis- 

 cussion and comment. It has been observed that the simplest form of 

 rate structure is the most desirable and is frequently commended for 

 this quality. 



Demand Charges on Portable Motors. 



An instance of this kind was referred to under Farm No. 7, and, as 

 already suggested, a charge per motor h. p. per month is to be dis- 

 couraged. Motors of 5 h. p. are at present used intermittently and at 

 infrequent intervals. 



Suggested Method of Establishing Demand. 



Of the many possible methods of establishing the rating basis or de- 

 mand of a farm, there seems to this investigator no more logical, ac- 

 curate and simple method than to employ the K. V. A. factor of the 

 transformer serving that farm. For example — a 1 K. V. A. trans- 

 former is required for a certain farm. 1 K. V. A., representing the 

 capacity of the transformer, also represents the demand the utility is 

 required to maintain for the farm, which can also be expressed in the 

 form of a demand charge in dollars and cents. By developing a scale 

 of demand ratings for various size transformers the demand charge 

 is immediately available without detailed study of the farm, its build- 

 ings, conditions, etc. 



This method appears to have much to commend it. The size of 

 transformer hung would correspond as nearly as possible to the esti- 

 mated or actual load of the farm in the interests of economy. No greater 

 load than this capacity (eliminating over-load capacity) could be used 

 continuously by the farm. This would also represent the maximum 

 demand the utility would have to supply. No other characteristics or 

 conditions on the farm such as acres, stock, buildings, etc., would be in- 

 volved. The problem is thus restricted to just the electrical load char- 

 acteristics and a classification of the individual as farmer, rural resi- 

 dent, etc., so that the corresponding rate could be applied. Transformer 

 capacities would appear on the work-orders so that they would be 

 readily accessible without farm inspections, etc. Where two or more 

 farms are served from one transformer, the K. V. A. capacity may be 

 divided between them according to connected load, demand meter read- 

 ings, or a similar method of adjustment. 



While disadvantages may show up in this method, several utilities 

 who have employed it for a year or two have reported none to date. 

 From the agricultural standpoint it reduces the possibilities of dis- 

 crimination to a minimum. 



